石墨烯作为一种新型二维碳材料，具有独特的结构特征和优异的电学、力学、光学以及热学性质，在储能、催化、传感器等领域有着良好的应用前景，引起了世界的广泛关注。廉价、可控制备石墨烯以及石墨烯材料的功能化修饰是制约其发展和应用的关键。 煤炭是自然界富存的以多环芳烃结构单元为主的含碳有机物，在新型碳材料制备中扮演着重要角色。本论文以煤炭为原料，针对煤基石墨烯的可控制备及其在光催化和电化学领域的应用进行了系统研究。在石墨烯制备方面重点研究了煤结构对煤石墨化过程的影响，探讨了影响煤基石墨烯结构和性能的主要因素；在应用方面重点考察了煤基氧化石墨烯复合材料在CO2光催化过程中的催化特性以及煤基石墨烯复合材料的电化学性能。相关研究结果对于开拓煤炭材料化利用的新途径，阐明影响煤基石墨烯结构和性能的因素具有重要的理论和应用价值。 首先，在煤基石墨烯制备方面，论文探讨了煤基石墨和煤基石墨烯制备的方法，以及影响石墨烯光催化特性和电化学性能的关键因素。煤经过不同石墨化工艺进行结构调变之后，进一步采用氧化法和低温等离子体还原技术可制得煤基石墨烯。研究结果表明：在2500℃及1500℃条件下，催化石墨化均可以实现煤有机大分子结构的有序化调变，使煤基石墨的石墨化度均可达到65%以上；当加入氯化铁/硼酸复合催化剂时，煤经过1500℃热处理后，可以使煤基石墨的石墨化度提高到71.63%。此外，不同变质程度的煤经催化石墨化后，其产物的石墨化程度也有差异，无烟煤因其有机大分子基本结构单元中芳香层片更大，因此更易石墨化。催化石墨化机理表现为硼元素削弱煤炭有机大分子结构中芳香层片之间桥键的交联作用，铁元素与分解得到的芳香层片相结合形成相应的碳化物，当催化剂中无序排列的炭达到饱和时，部分炭以低能级的石墨化碳结晶形态沉积下来形成煤基石墨。 其次，系统研究了ZnO/煤基氧化石墨烯复合材料在CO2光催化还原过程中的应用。本研究以煤基氧化石墨烯为基材，通过共沉淀法制备了ZnO/煤基氧化石墨烯复合材料，考察了煤基氧化石墨的结构及ZnO负载量对复合材料光催化CO2还原过程的影响。研究结果表明：不同负载量的ZnO/煤基氧化石墨烯复合材料对CO2的光催化还原均具有一定光催化作用，其在可见光区的催化活性和选择性明显优于紫外光区，煤基氧化石墨烯结构及特性是影响ZnO/煤基氧化石墨烯复合材料的光催化活性和选择性关键因素；在可见光作用下，ZnO/煤基氧化石墨烯复合材料的光催化活性表现为ZnO/KCGO复合材料> ZnO/TXGO复合材料>ZnO/JCGO复合材料（复合比为7:3，添加量1g/L），并且对甲酸有较高的选择性，产物中甲酸产率与甲醇产率之比最高可达35.36。这主要是由于煤基氧化石墨烯的加入，其自身较大的间隙能，增强了该复合材料在可见光区的吸收能力，同时有助于促进光生电子的还原能力。 最后，本论文研究了煤基石墨烯及MnO2/煤基石墨烯复合材料在超级电容器电极材料中的应用，分析了煤基石墨烯片层大小和结构缺陷对煤基石墨烯及其复合材料电化学性能的影响。当煤基石墨烯材料用作超级电容器正极材料时，其首次充放电比电容量的高低顺序为：GG>KCG>>TXG>>JCG；当MnO2/煤基石墨烯复合材料用作超级电容器正极材料时，首次充放电的比电容量值相较于煤基石墨烯有了很大提高，这是因为石墨烯片层结构与线性二氧化锰复合时产生了强烈的协同效应，使复合材料展现出优异的导电性能；煤基石墨烯的结构不同，其与二氧化锰协同效应的大小也有差异，其中，MnO2/TXG复合材料的电化学性能提高最明显，首次充放电的比电容量达到159.05 F/g ，是TXG比电容量的3倍多。这主要归因于TXG具有更大的石墨烯层片结构，使二氧化锰纳米棒更易均匀分散在煤基石墨烯层片间，从而形成通畅的电子传输通道，提高了复合材料导电性能。

Attributed to the unique two-dimensional crystal sp2carbon structure, graphene has exhibited extraordinary mechanical, electrical, and optical properties. These properties give graphene great potential applications in functional materials, catalysts, sensors, and plenty of other fields. However, the key factors on the development and application of graphene are due to its controllable production and functionalization. As a natural carbon source, coal, containing polycyclic aromatic hydrocarbons, plays an important role in the preparation of various new carbon materials. With the purpose of controllable preparation and application of graphene using coal as a raw carbon source, this thesis focuses on studying the factors which significantly affect the structure and properties of graphene, including the coal structure, graphitization degree, coal powder size and coal type. The main work is to investigate the coal-based-graphene composite materials and study their applications in CO2 photocatalytic process and electrochemical performance. These results have demonstrate dimportant theoretical and practical valueby clarifying main factors that affect the structure and properties of graphene, which will open a new way for applying coal as acarbon source material for large-scale production of graphene and graphene-based different applications. First, the key factors on the graphitization of coal and production of grapheme are studied. A novel technology is developed to prepare grapheme from coal as a source material, which includes graphitization and chemical oxidation combined with plasma reduction. The results show that the organic macromolecular structure of coal is modulated by catalytic graphitization at 2500°C and 1500°C ，and the graphitization of coal-based-graphites is higher than 65.0%. Specifically, the graphitization of coal-based-graphites is further increased to 71.63% by combining a heat-treatment at 1500°C with ferric chloride/boric acid as a catalyst. Therefore, the graphitization productivity significantly depends on the coal sources. The graphitization product with anthracite as raw material is easily graphitized because of their large-scale aromatic layers in organic molecule structural unit. The mechanism of coal catalytic graphitization shows that boron atoms weaken the crosslink of bridges between aromatic layers in coal. The corresponding carbides were obtained due to the chemical reaction between iron and the aromatic layers, and when disordered carbon become saturated, carbon partially deposited and formed coal-based-graphite at low energy level. Furthermore, ZnO/graphene-oxide composites are fabricated and applied as catalysts in CO2 photocatalytic process study. The results demonstrate that ZnO/graphene-oxide composites, which are obtained from ZnO and different coal source produced grapheme oxide, shows effective performance in CO2 photocatalytic process and the superior catalytic activity as well as selectivity in the visible region is higher than in the ultraviolet region. The key factors are found to attribute to the structure and characteristics of grapheme oxide. The catalytic activity follows ZnO/KCGO composites >ZnO/TXGO composites >ZnO/JCGO composites while the mass ratio between ZnO and coal-based-graphene-oxide is 7:3 and the addition was 1g/L. The formic acid had high selectivity and is 34.36 times higher than the yield of methanol. The main reason that absorption capacity of composites in visible region is enhanced is due to the coal-based-graphene-oxide having high band gap energy, and it further improves the reducing ability of photo-electrons. Finally, the coal-based-graphene composites are employed in supercapacitors. The sheet size effects and structural defects of coal-based-graphene are systematically investigated. The first charge-discharge capacity order is GG>KCG>>TXG>>JCG when graphene is used as cathode material. Then, the electrical performance of MnO2/graphene composites is studied. The results show that the first charge-discharge capacity of MnO2/graphene composites has greatly improved compared to the pure MnO2 and graphene. The strong synergy is generated due to MnO2 and coal-based-graphene compound having excellent electrical properties. The electrical property of MnO2/TXG composite is increased remarkably and the first charge-discharge capacity reaches 159.05 F/g, which is 3 times higher than TXG. This is mainly due to TXG having larger graphene sheet than the other coal-based-graphene, and the MnO2 dispersing into graphene layers evenly to form a smooth electron transport channel to improve the electrical performance of MnO2/TXG composite.